Research On Multiuser Detection For Future Mobile Communication System

With the development of world mobile communication technology has made substantialprogress. Telecommunications industry of China developed rapid after3G implement inChina. The third generation standards that International Telecommunication Union hasaccepted are mainly three kinds of following standards: WCDMA, CDMA2000andTD-SCDMA which base on the technology of CDMA. Furture mobile communication systemwill be a advanced system which based on3G. Since CDMA is an interrupted and restricedsystem, its capacities and the function are restricted by multiple addresses interrupt, whilemultiuser detection can reduce much of the interrupts of multiple addresses and it canimprove the capability of users. Multiuser detection is one of the key technologies in futuremobile communication systems.Voice service is the main object to detect in the existing mobile communication systems.The system only realized packet transmission of the data service. Future mobilecommunication systems will achieve full packet transmission in response to discreteinformation and high randomness. BS can track user`s location because P domain service willalways online. This paper propose a multiuser detection plan of full packet transmission forfuture mobile communication systems. Taking into account the delay requirements of voiceand the bit error rate must be below10-3, the system use PIC to delete the multiuser interferes.The system revert the multiuser interferes with the first demodulate singals. Then delete themultiuser interferes to improve the accuracy of the users. Smart antenna can track the locationof the packet singals because P domain service is always online. The smart antenna adjust thedirection of main beam to achieve a maximum gain for desire user.The research validated the detect system by numerical simulations. Wireless channelenvironment and the minimum technical requirements of ITU-2135technical specificationswere realized by computer simulation. The simulation system include multipath fanding andnoise factors and the receiver equalize the interfere which come from wireless channel.This paper realized the multiuser detection of full packet singals by computer simulations. The simulation results show that the full packet singals multiuser detection realized the biterror rate request of communication system. This paper proposed a theoretical model andmuch analysis. The simulation results show that it is a feasible project. It will be helpful tofurture mobile communication systems.